Private Sub Command1_Click()
Dim str1() As String
Dim str2() As String
Dim arr() As String
Dim rows As Integer
Dim cols As Integer
Dim i As Integer
Dim j As Integer
Open "c:\in.txt" For Input As #1
rows = 0
Do Until EOF(1)
rows = rows + 1
ReDim Preserve str1(rows) As String
Line Input #1, str1(rows)
cols = UBound(Split(str1(rows), ","))
Loop
Close #1
ReDim arr(rows, cols) As String
For i = 1 To rows
str2 = Split(str1(i), ",")
For j = 0 To cols
arr(i, j) = str2(j)
Print "arr(" & i & "," & j & ")=" & arr(i, j),
Next
Print
Next
End Sub

根据你的题意自创了个in.txt文件，40组数据，未发现报错，检查下你的in.txt文件，或提供你的in.txt文件调试下就知道了。

1,1,0,0,2,0,3,3，
2,3,0,0,5,3,3,3，
这就是in.txt内容  谢谢

真不好意思，还是没有发现错误，见下图：

【，】
【,】

仔细看了你们的代码。
代码的流程无问题，问题出在数据文件上，存在空行，而代码里没有容错处理，导致下标越界。


Private Sub Command1_Click()
Dim str1() As String
Dim str2() As String
Dim arr() As String
Dim rows As Integer
Dim cols As Integer
Dim cols2 As Integer              '增加一个变量
Dim i As Integer
Dim j As Integer
Open "C:\in.txt" For Input As #1
rows = 1
Do Until EOF(1)
'rows = rows + 1              '移到后面处理
ReDim Preserve str1(rows) As String
Line Input #1, str1(rows)
cols = UBound(Split(str1(rows), ","))          '找每次的下标
If cols2 < cols Then cols2 = cols              '保存最大的下标
If Len(str1(rows)) > 0 Then rows = rows + 1    '因为存在空行，所以空行不计数，直接跳。如果数据的最后有空行，会导致最后多一个空行。
Loop
Close #1
ReDim arr(rows, cols2) As String               '按最大下标生成数组，前面的代码，如果空行在最后，那么这里报错。
For i = 1 To rows
str2 = Split(str1(i), ",")
For j = 0 To UBound(str2)                      '按当前下标复制数据。前面的代码，如果空行在中间，那么这里报错。
arr(i, j) = str2(j)
Print "arr(" & i & "," & j & ")=" & arr(i, j),
Next
Print
Next
End Sub

好吧，的确应该像7楼版主那样考虑下极端情况，要有一定的容错能力。不过应该是使用最小的cols，如果像7楼那样使用最大的cols的话，对少于cols的行split就会产生下标越界的错误，修改后的代码如下：
Private Sub Command1_Click()
Dim str1() As String
Dim str2() As String
Dim arr() As String
Dim rows As Integer
Dim cols As Integer
Dim i As Integer
Dim j As Integer
Open "c:\in.txt" For Input As #1
rows = 0
Do Until EOF(1)
rows = rows + 1
ReDim Preserve str1(rows) As String
Line Input #1, str1(rows)
i = UBound(Split(str1(rows), ","))
If cols > i Or cols <= 0 Then cols = i
Loop
Close #1
ReDim arr(rows, cols) As String
For i = 1 To rows
If str1(i) <> "" Then
str2 = Split(str1(i), ",")
For j = 0 To cols
arr(i, j) = str2(j)
Print "arr(" & i & "," & j & ")=" & arr(i, j),
Next
Print
End If
Next
End Sub

这是我的in 文件 但是我怎么弄都不对 我觉得是这个TXT文件的原因 但是找不出来  

没看懂什么意思。

你提供的附件里的文件，正常的很，没任意问题啊。